VATICAN CITY — For four days, some of the world’s highest-ranking Catholics listened to speeches about the “outrage of the people” and the imperative of action. They heard testimony from abuse victims, including one who movingly played the violin. And on Sunday, they gathered in a frescoed Vatican hall, where Pope Francis concluded the summit on clerical sexual abuse by calling for an “all-out battle” against the scourge.

But the unprecedented meeting ended Sunday with few concrete remedies, and it left the Catholic Church much where it started at the beginning of the week: asking for more time from an impatient faithful to draw up ways to reliably police itself.

“We are dealing with abominable crimes that must be erased from the face of the earth,” Francis said in a speech that was short on specifics but mentioned future “legislation.”

The vague outcome underscored the looming challenge for an institution that has long acknowledged the seriousness of clerical abuse but struggled to curtail it. While some participants said the event would prove to be a turning point, many victims said it had amounted to a training seminar that skirted key decisions and raised points that should have been obvious years ago.

“I don’t think we can rely on the institution to clean up its act,” said Peter Saunders, a British sex abuse survivor and former member of Francis’s commission on the protection of minors.

Since the clergy abuse scandal first exploded onto the scene in the United States in 2002, the Vatican has seen cases emerge in nearly every corner of the world with the means to investigate. Thousands of priests have been disciplined by the Holy See, but even that figure doesn’t account for the scale of the problem, as many accusations are never reported to Rome.

The Argentine pontiff announced the summit in September while facing abuse-related scandals on multiple continents — stemming from cases that had damaged his own reputation and further abraded the church’s credibility. At the start of the event, Francis called for “concrete and effective measures” to contend with the problem. And though some of the Vatican’s handpicked speakers described their proposals in detail, any follow-through will have to come in the months and years ahead, if at all. Several U.S. bishops pledged Sunday to improve their own guidelines at a June meeting.

The event organizers have said they will remain in Rome in the coming days to discuss some of the ideas aired at the summit. Archbishop Charles Scicluna, of Malta, noted that Francis on Thursday handed out “21 reflection points” — ideas for action the church can potentially take against abuse. After a group discussion session, some bishops responded with 21 ideas of their own.

“We need to bring all of this together when we’re discussing follow-up,” Scicluna said.

In his remarks Sunday, Francis spoke in sweeping terms about abuse, describing the underlying reasons that victims are fearful about speaking out and the fallout they face as adults, including “bitterness” and “suicide.” Parts of his speech — which was heavily footnoted with data from international organizations — had little to do with the church, and he mentioned how abuse can take place within families, schools and athletic facilities, and how the digital world adds new dangers for young people.

Abuse is a “worldwide phenomenon,” Francis said, but it is “all the more grave and scandalous in the church,” incompatible with its “moral authority and ethical credibility.”

Francis said the church would “spare no effort to do all that is necessary to bring to justice” anyone who has committed the “crimes” of abuse. But he did not mention a zero-tolerance policy, favored by many Catholics, that would force priests found guilty of child abuse to be removed automatically from ministry. Though some countries, including the United States, have such zero-tolerance guidelines on the books, it is not an across-the-board church practice.

After Francis’s speech, the Vatican said it would publish a guidebook for bishops that will help them understand their “duties and tasks” on abuse. The Vatican also said it would create new child-protection laws for its own city-state — rules that cover the 110-acre space near the Tiber River but not the universal church. Pressed on the matter, a Vatican spokesman said those new laws have been in the works for months and are not a direct result of the summit.

Larger questions, including how the church will handle the investigation and discipline of bishops accused of misconduct, remain unresolved — though key developments could be on the horizon. Vatican officials have said Francis will soon “clarify” a 2016 church law that was drawn up to hold bishops accountable for negligence, something the Vatican has long struggled to do. On Friday, Cardinal Blase Cupich, of Chicago, laid out his own plan for improving the oversight of bishops, urging, among other steps, that lay people be involved in investigations.

Prelates in the United States have pushed for new ways to regulate the behavior of bishops in the wake of bruising abuse revelations about recently defrocked former cardinal Theodore McCarrick, who rose through the ranks of the faith even as rumors swirled about his behavior. The Vatican in November stopped the U.S. bishops at their annual meeting from voting on new steps to hold bishops more responsible in abuse cases. A Vatican cardinal later indicated, in a letter obtained by the Associated Press, that there were problems with the U.S. proposals. But some American Catholics say the Vatican thwarted a potential improvement of current U.S. church anti-abuse guidelines.

In a statement issued Sunday, Cardinal Daniel DiNardo, the president of the U.S. Conference of Catholic Bishops, said the U.S. church would go forward with ideas “in communion with the Holy See” and consider them at a meeting in June.

“Achieving these goals will require the active involvement and collaboration of the laity,” DiNardo said.

One American bishop, Shawn McKnight, of Jefferson City, Mo., who was not in Rome, called the summit a “cathartic moment for the global church.”

McKnight and Baltimore Archbishop William Lori, who have been vocal about holding top church leaders accountable, said Sunday in separate telephone interviews that the summit smoothed the path for the U.S. church to pass concrete measures when all American bishops meet again in June.

“I think we can look at what was proposed last November, flesh it out, recognize how it relates not only to our local situation but to the whole church, and then put something together that will probably be better thought out and will do more good in the long run,” Lori said. “I wasn’t happy in November that we couldn’t do what we attempted to do, but I’m now hopeful we will do the job better come June. That’s my hope and prayer. That’s the signal we’re getting from Rome.”

Lori said the difference since November has been spiritual — U.S. bishops having a week-long spiritual retreat in January that the pope called for, and to be led this past week by a Jesuit, an order that focuses on discernment and prayer.

“In America we want the quick fix, the rule, the law, and this has a real sense of urgency,” Lori said. “I think [Francis] is also asking us to step back to pray and reflect and discern and get it right.”